Formulation and development of bicontinuous nanostructured liquid crystalline particles of efavirenz

Liquid Crystalline Nanoparticles as an Ophthalmic Delivery System for Tetrandrine: Development, Characterization, and In Vitro and In Vivo Evaluation

The purpose of this study was to develop novel liquid crystalline nanoparticles (LCNPs) that display improved pre-ocular residence time and ocular bioavailability and that can be used as an ophthalmic delivery system for tetrandrine (TET). The delivery system consisted of three primary components, including glyceryl monoolein, poloxamer 407, and water, and two secondary components, including Gelucire 44/14 and amphipathic octadecyl-quaternized carboxymethyl chitosan. The amount of TET, the amount of glyceryl monoolein, and the ratio of poloxamer 407 to glyceryl monoolein were selected as the factors that were used to optimize the dependent variables, which included encapsulation efficiency and drug loading. A three-factor, five-level central composite design was constructed to optimize the formulation. TET-loaded LCNPs (TET-LCNPs) were characterized to determine their particle size, zeta potential, entrapment efficiency, drug loading capacity, particle morphology, inner crystalline structure, and in vitro drug release profile. Corneal permeation in excised rabbit corneas was evaluated. Pre-ocular retention was determined using a noninvasive fluorescence imaging system. Finally, pharmacokinetic study in the aqueous humor was performed by microdialysis technique. The optimal formulation had a mean particle size of 170.0 ± 13.34 nm, a homogeneous distribution with polydispersity index of 0.166 ± 0.02, a positive surface charge with a zeta potential of 29.3 ± 1.25 mV, a high entrapment efficiency of 95.46 ± 4.13 %, and a drug loading rate of 1.63 ± 0.07 %. Transmission electron microscopy showed spherical particles that had smooth surfaces. Small-angle X-ray scattering profiles revealed an inverted hexagonal phase. The in vitro release assays showed a sustained drug release profile. A corneal permeation study showed that the apparent permeability coefficient of the optimal formulation was 2.03-fold higher than that of the TET solution. Pre-ocular retention capacity study indicated that the retention of LCNPs was significantly longer than that of the solution (p < 0.01). In addition, a pharmacokinetic study of rabbit aqueous humors demonstrated that the TET-LCNPs showed 2.65-fold higher ocular bioavailability than that of TET solution. In conclusion, a LCNP system could be a promising method for increasing the ocular bioavailability of TET by enhancing its retention time and permeation into the cornea.

Efavirenz Self-Nano-Emulsifying Drug Delivery System: In Vitro and In Vivo Evaluation

Self-emulsifying drug delivery system (SEDDS) is the isotropic and thermodynamically stable mixture of oil, surfactant, co-solvent/surfactant, and drug. It emulsifies spontaneously when introduced into an aqueous phase under a mild agitation. The current study was aimed to prepare SNEDDS to augment solubility, release rate, and oral bioavailability of BCS class II drug, efavirenz (EFV). A series of oil, surfactant, and co-surfactant was screened out by a ternary phase diagram to locate a better homogenous mixture. The prepared SNEDDS was evaluated regarding its appearance, mean droplet size, phase separation, in vitro drug release, and oral bioavailability. Among the screened oil, surfactant, and co-surfactant, Labrafil M 2125 CS, Tween 80, and Transcutol®P mixture exhibited superior solubilizing capacity, respectively. Optimized SNEDDS exhibits 98.39% drug release. SNEDDS dissolution behavior was attributed to oil/surfactant ratios and properties of the surfactant phase. It also demonstrates threefold increments in the area under curve (AUC) in comparison to neat EFV. Furthermore, the optimized SNEDDS does not show any vitrification during its 3-month storage. In the present study, better performance of SNEDDS is explained by various factors like (i) improved surface area of droplets, (ii) superior solubilization potential for hydrophobic drugs due to Labrafil M 2125 CS, and (iii) result of surfactant on mucosal permeability. This study demonstrated that SNEDDS may be an alternative approach for the poorly soluble drugs to improve their solubility and oral bioavailability.

Nanostructured lipid carrier mediates effective delivery of methotrexate to induce apoptosis of rheumatoid arthritis via NF-κB and FOXO1

Present study was designed to develop novel nano-structured lipid carriers (NLCs) formulated by lipid mixture and chemical permeation enhancer-based hydrogel for an effective transdermal delivery of methotrexate (MTX). The prepared NLCs were optimized with different preparative variables such as particle size <200 nm, poly-dispersity index (PDI) <0.2, and entrapment efficiency ∼85%. The drug incorporated into NLCs-gel base showed excellent spread ability without any grittiness during rheological behavior and texture profile analysis. The in vitro release showed biphasic release pattern with initial fast release of drug (>50%) in 8h followed by sustained release (up to 85%) by the end of 48thh. NLCs showed greater uptake in human hyper-proliferative keratinocyte cell line (HaCaT). NLCs showed increased expression of inflammatory mediators as well asapoptosis in U937 monocytic cells. The greater expression of pro-apoptotic gene Bim regulated by NF-κB-IkB and FOXO1 is supported by fold regulations calculated for various apoptotic and pro-inflammatory biomarkers carried out by RT-PCR. The immunocytochemistry to detect IL-6 expression and immunofluorescence assay suggested that induced apoptosis occurs in experimentally induced in vitro arthritis model treated with NLCs-MTX. We saw reduced inflammation and triggered apoptosis through NF-κB & FOXO1 pathways induced by MTX loaded NLCs in rheumatoid arthritic cells. In addition, formulated NLCs exhibit better skin permeation with higher permeation flux & enhancement ratio as shown by confocal laser scanning microscopy (CLSM). Moreover, histopathological examinations of skin are suggestive of safety potential of NLCs.

Quality-by-design based development of a self-microemulsifying drug delivery system to reduce the effect of food on Nelfinavir mesylate

Poor aqueous solubility and moderate permeability of Nelfinavir mesylate (NFM) leads to high variability in absorption after oral administration. To improve the solubility and bioavailability of NFM, the self microemulsifying drug delivery system (SMEDDS) was developed. For this purpose, Quality by design (QbD) approach employing D-optimal mixture design was used to prepare SMEDDS of NFM. Further, the software generated numerically optimized SMEDDS were developed by utilizing desirability function. Maisine 35-1, Tween 80, and Transcutol HP were identified as oil, surfactant, and co-surfactant that had best solubility for NFM. Ternary phase diagrams were plotted to identify the self-emulsification region. Dissolution of putative NFM in simulated fasted or fed small intestinal conditions, respectively, predicted that there is a positive food effect. However, NFM loaded SMEDDS showed absence of food effect with no significant difference in dissolution performance either in Fasted or fed state simulated intestinal fluid (FaSSIF or FeSSIF) biorelevent dissolution media. The prepared SMEDDS were thermodynamically stable with droplet size (121 nm), poly dispersity index (PDI) (0.198) and emulsification time (<1 min). Transmission electron microscopy (TEM) analysis confirmed the spherical shape of the reconstituted SMEDDS droplets. The ex vivo performance revealed 4.57 fold enhancement in the apparent permeability of NFM as compared to NFM suspension. The animal pharmacokinetic analysis in New Zealand strain rabbits indicated food effect on pure NFM suspension. However, absence of food effect and 3.5-3.6 fold enhancement in the oral bioavailability was observed when NFM was formulated into SMEDDS. Thus, it could be envisaged that development of SMEDDS formulation of NFM could be one of the best alternative to enhance oral bioavailability of NFM.

Cubosomes: remarkable drug delivery potential

Cubosomes are nanostructured liquid crystalline particles, made of certain amphiphilic lipids in definite proportions, known as biocompatible carriers in drug delivery. Cubosomes comprise curved bicontinuous lipid bilayers that are organized in three dimensions as honeycombed structures and divided into two internal aqueous channels that can be exploited by various bioactive ingredients, such as chemical drugs, peptides and proteins. Owing to unique properties such as thermodynamic stability, bioadhesion, the ability of encapsulating hydrophilic, hydrophobic and amphiphilic substances, and the potential for controlled release through functionalization, cubosomes are regarded as promising vehicles for different routes of administration. Based on the most recent reports, this review introduces cubosomes focusing on their structure, preparation methods, mechanism of release and potential routes of administration.

Sterically stabilized spongosomes for multidrug delivery of anticancer nanomedicines

SAXS patterns of drug-loaded lipid nanocarriers stabilized by polysorbate P80 (left); cryo-TEM image of BAI-BJO-spongosomes-2 (right).